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From Henry JunYoung KIM <henry.jy...@gmail.com>
Subject Re: HRegionInfo returns empty values.
Date Mon, 22 Oct 2012 00:15:27 GMT
I want to extract a start-key and an end-key of a region ;) 

for a start key, a scanner is enough I think without arguments. 
then it returns a single row which is a start-key of a region. 

for a end key, I don't know. maybe I need to track it and keep it continuously. 
right?


2012. 10. 19., 오후 6:07, "Ramkrishna.S.Vasudevan" <ramkrishna.vasudevan@huawei.com>
작성:

> What is your need? You want to scan the rows i.e data in the table? 
> Or you want to start and endkeys.  Actually for single region just empty
> bytes represent the start and endkey.  So am not getting what you want from
> that.
> 
> If you want data then create a scan object for the table and do a scan :)
> Rgards
> Ram
>> -----Original Message-----
>> From: Henry JunYoung KIM [mailto:henry.jykim@gmail.com]
>> Sent: Friday, October 19, 2012 2:34 PM
>> To: user@hbase.apache.org
>> Subject: Re: HRegionInfo returns empty values.
>> 
>> yes, right ;)
>> 
>> currently, I have just a single region.
>> 
>> in this case, to get a start-key and and end-key, I need to use just a
>> scanner. right?
>> 
>> 2012. 10. 19., 오후 5:51, "Ramkrishna.S.Vasudevan"
>> <ramkrishna.vasudevan@huawei.com> 작성:
>> 
>>> Can you tell me how the splitkeys are formed when the table was
>> created?
>>> Or there are no splits at all for your table?  If there are no splits
>> then
>>> you will get empty start and endkey.
>>> 
>>> Regards
>>> Ram
>>> 
>>>> -----Original Message-----
>>>> From: Henry JunYoung KIM [mailto:henry.jykim@gmail.com]
>>>> Sent: Friday, October 19, 2012 2:13 PM
>>>> To: user@hbase.apache.org
>>>> Subject: HRegionInfo returns empty values.
>>>> 
>>>> Hi, hbase-users.
>>>> 
>>>> To get a start-key and end-key from each region, I implemented
>> simple
>>>> code like this.
>>>> 
>>>> 
>>>> 
>>>> 	HTable table = new HTable(admin.getConf(), admin.getTableName());
>>>>       NavigableMap<HRegionInfo, ServerName> locations =
>>>> table.getRegionLocations();
>>>>       for (Map.Entry<HRegionInfo, ServerName> entry:
>>>> locations.entrySet()) {
>>>>           HRegionInfo info = entry.getKey();
>>>> 
>>>>           System.out.println("server : " +
>>>> entry.getValue().getHostname());
>>>>           System.out.println("start : " +
>> info.getStartKey().length);
>>>>           System.out.println("end : " + info.getEndKey().length);
>>>> 	}
>>>> 
>>>> 
>>>> but, this code returns
>>>> 
>>>> server : one-of-servers-name
>>>> start : 0
>>>> end : 0
>>>> 
>>>> start-key and end-key is empty. nothing!
>>>> data size is very strong. it's about 10,000.
>>>> from integer 0 to integer 10,000.
>>>> 
>>>> how could I get correct range of a region?
>>>> 
>>>> thanks for your concerns.
>>> 
> 


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